5.1.5 %?... Special Texts

The text part of a resource file line may be provided with different special
texts which may occur in any1 number and order. All these
texts start with a ‘%’ (percent) character which may be protected by a
leading ‘\’ (backslash) character if the ‘%’ (percent) character
itself is wanted to be used in the text part, e.g. ‘\%’. The ‘%’
character is mostly trailed by an optional format instruction, (see
Format Instruction,
for the detailed description of the format instruction and its components),
and then trailed by a distinguishing mark —which defines the kind of the
special text to be used— and if it is a letter, Gcal accepts
it case-sensitive.

The purpose of these special texts is mainly to suppress output of fixed
dates in definite cases, either, or to provide them with particular texts
respectively to start external commands.
See Description of all %?... Special Texts,
for a complete description of all usable special texts, and
Summary of all %?... Special Texts,
for an according short-list of them.